Atomic irradiator having means for rotating samples for uniform exposure

ABSTRACT

A thick-walled housing of radioactive absorbing material has an enlarged cavity which contains a solid movable block. A radiation source compartment is centrally disposed within said housing and immediately adjacent said block. A radiation compartment is disposed within said block and can be moved into and out of alignment with the radioactive source. This compartment can also be moved into and out of alignment with an exterior access opening through the housing so that articles can be placed within the radiation compartment and subsequently moved to the interior of the housing and into alignment with the radiation source. The compartment has a movable turntable therein which permits the article to be uniformly exposed on all sides to the radiation source.

Aug. 8, 1972 United States Patent Packin et al.

ATOMIC IRRADIATOR HAVING [54] Primary Examiner-Archie R. Borchelt MEANS FOR ROTATING SAMPLES At rney-Burt0n Scheiner FOR UNIFORM EXPOSURE [57] ABSTRACT A thick-walled housing of radioactive absorbing [72] Inventors: Milton Packin, Livingston; Bernard Seid, Ceder Grove, both of NJ.

I material has an enlarged cavity which contains a solid [73] Asslgnee: Mach'nery Corpmatm" movable block. A radiation source compartment is Filed: Oct. 16, 1967 Appl. No.: 675,578

centrally disposed within said housing and immediately adjacent said block. A radiation compartment is disposed within said block and can be moved into and out of alignment with the radioactive source. This 52 US. c1................2s0/52, 250/106 s, 250/108 R cmpaflmem can also be moved into and out of align- 51 Int. 5/00 106,106 s,10s

ment with an exterior access opening through the housing so that articles can be placed within the radia tion compartment and subsequently moved to the in- [58] Field of Search........250/5l, 52,

terior of the housing and into alignment with the [56] References Cited radiation source. The compartment has a movable turntable therein which permits the article to be UNITED STATES PATENTS uniformly exposed on all sides to theradiation source.

3,506,825 4/1970 Hartmann. .,.................250/52 15 Claims, 7 Drawing Figures PATENTED AUG 8 1972 SHEET 1 0F 3 5 m mm WP n M Ber/70rd 52/0 i92 S6 98 9O 54 ATTORNEYS PATENTEDAus 81972 lnven/ors Mil/on Pack/h Bernard Se/d M Wi 4% ATTORNEYS bhL,

SHEET 3 0F 3 ATOMIC IRRADIATOR HAVING MEANS FOR ROTATING SAMPLES FOR UNIFORM EXPOSURE radiation chamber when it is facing the radiation source.

A still further object of this invention is to provide means for easily moving the radiation chamber into position with either the radiation source or the access opening through the housing.

Other objects and advantages of my invention reside in the details of construction, arrangement, and combination of the various parts of my apparatus as hereinafter more fully set forth, as specifically pointed out in my claims, and illustrated in the accompanying drawings, in which: I

FIG. 1 shows a front elevational view of the radiation unit;

FIG. 2 is a side cross-sectional view of the unit illus- 'tratin g the operative parts thereof;

FIG. 3 is a cross-sectional view along the plane defined by line 3 3 of FIG..2 illustrating the shape and alignment of the major parts of the unit;

FIG. 4 is a bottom view of the housing;

FIG. 5 is a cross-sectional view of the radiation chamber showing in detail the sample rotating driving assembly;

FIG. 6 is a side cross-sectional view of the unit illustrating an alternative drive mechanism;

FIG. 7 is a cross-sectional view along the drive belt shown by line 6 6 of FIG. 7 illustrating the alternative turntable drivearrangement.

Referring to the drawings, FIG. 1 shows a housing generally indicated at 10 which is supported by legs 12 connected by cross pieces 14. Metal ring 16 isintegral with the top of the housing to facilitate handling of the unit with lifting equipment.

A control box 20 having a turn lever .22and a motor control switch 24 is mounted directly below the housmg.

Housing 10 has an access opening v26 into which a sample to be exposed to radiation ispassed.

A more detailed showing is illustrated in FIGS. 2 and 3, wherein the housing 10 consists of a large mass 28 of radiation absorbing material such as lead encased in a steel sheathing 30.

Internal circular cavity 32 having an upper recess 33 i and a lower recess 34 contains a rotatable block 36 having protuberances complementary to the recesses 33 and 34 so as to provide substantially non-planar top and bottom surfaces on the rotatable block 36. The block 36 is formed of radiation absorbing material which has a lower bearing protrusion 37 and a socket 38. The rotatable block 36 is freely movable and supported within the cavity on socketmember 38, rotating in response to rotational movement imparted to the socket member 38.

tion 96. The turntable 52 is held in An elongated passage40 extends up from the bottom of the housing 10, communicating with the large internal cavity 32. A bearing 42 is disposed within the passageway to support the shaft 44 which has a lug 45 which extends into the socket 38. Shaft 44 has a lower reduced diameter section 46 with a shoulder 47 which receives ball bearing 48.

The rotatable block 36 has a radiation chamber 50 in which a sample to be exposed to radiation is placed. A turntable .52 is mounted therein. In FIG. 2 it can be seen that the turntable 52 has an vupturned edge 53 and a central hub 54. A ball bearing 56 mounted within the turntable drive chamber 58 directly supports the central hub 54 ofthe turntable 52.

A radiation source chamber 60 is centrally located within the housing 10 and has a vertically extending radiation opening 62 which connects with the enlarged cavity 32. A radiation source 64 is disposed therein.

The turning assembly for the rotatable movable blockis specifically shown in FIG. 2.

The depending shaft and lever support sleeve 72 is integral with the bottom of the casing and in alignment with shaft 44.

An externally threaded bearing retainer 74 is fitted therein and supports ball bearing 48. The rotatable block turn lever 22 illustrated in FIG. 1 has a circular end section 76 disposed on the end of the lower end section46 of shaft 44.

Retaining cross pin 77 engages shaft section 46 through a slotted hole 46a in the shaft permitting lever 22 to be moved along the axis of the shaft. Pin 79 acts as a stop. Pin 78 is engaged by pin 77 when lever 22 is moved upwards, thereby locking the lever in position. A hole through shaft section 46 below the lever 22 permits insertion of a padlock or straight pin to hold lever 22 in the locked position. This prevents rotation of block 36. Rotational movement of end piece 76 will turn shaft 44 and thereby move rotatable block 36 to change the position of the radiation chamber 50 with respect to either the sample access opening 26 or the radiation source chamber 60.

A motorand gear assembly generally indicated at 80 is disposed immediately below an elongated passageway 82 which extends from the bottom of casing 10 adjacent the motor and gear assembly up to the tumtable drive chamber 58. An elongated turntable drive shaft extends through the passageway .82 and has a lower ending 85 which engages the turntable motor drive and gear assembly '80. The upper end 86 of the shaftis chamfered and level with the adjacent cavity surface 88.

The turntable drive shaft engaging assembly is shown in greater detail in FIG. 5. The turntable 52 is directly mounted on an adapter piece 90 having a peripheral shoulder 92 which engages bearing 56. It also has a lower stud section 94 and a spring retaining recess secposition on the adapter piece 90 by screw 98.

A drive shaft engaging sleeve has in upper stud receiving section 102 telescopically mounted on the stud 94. The two pieces may have a shape or have a key slot arrangement to prevent relative rotation between them.

The turntable drive shaft engaging sleeve 100 has a chamfered solid lower end 104 which directlyengages the drive shaft end 86 when the radiation chamber is in aligned position with the radiation source 64.

The drive shaft engaging sleeve 100 has a shoulder 106 adjacent its lower end on which the lower end of a spring 110 is mounted. The spring fits over the outside of the slidable drive shaft engaging sleeve 100 and has its upper end within the spring retaining recess section 96 of the adapter piece 90 so that a downward spring bias is applied to the slidable drive shaft engaging sleeve 100 to keep its chamfered lower end 104 in frictional engagement with the chamfered end 86 of the elongated turntable drive shaft 84.

To operate the unit, the turn lever 22 is freed for movement by removing the padlock or pin from slotted opening 42 immediately below the cross pin 77, permitting it to drop downwardly and clear of locking pin 78. The turn lever 22 is moved to the left as viewed in FIG. 1. This moves the radiation chamber 50 into alignment. with the access opening 26.

The specimen to be exposed to radiation is then placed on the turntable 52. The turn lever is then moved to the right as shown in FIG. 1 until the cross pin 77 engages the stop pin 79. At this position the radiation chamber 50 will be facing the radiation source compartment 60 and the sample on the turntable 52 will be exposed to the radiation passing through the radiation window 62. It will be noted that turning movement of the lever 22 is transmitted through the cross pin 77 to the elongated shaft 44. Rotation of shaft 44 rotates the rotatable block 36 on its axis through the socket 38.

Movement of the rotatable block swings the turntable drive assembly which is disposed immediately below the radiation chamber, along the surface 88 to a point immediately above the turntable drive shaft 84. At this point the drive shaft engaging sleeve 100 is forced by the spring 110 downwardly into firm frictional engagement with the upper end 86 (FIG. 5) of turntable drive shaft 84 to give a firm frictional drive connection. Rotation of the turntable drive shaft is affected by the turntable motor and gear assembly 80. The drive shaft engaging sleeve 100 rotates, thereby rotating adapter piece 90 on which turntable 52 is directly fastened.

The motor control switch 24 shown in FIG. 1 controls operation of the turntable motor and gear assembly 80.

After the specimen on the turntable has been exposed to radiation for the desired length of time, the motor control switch 24 is turned off, and the turn lever 22 moved to again rotate the movable block 36 to the outer position where the radiation chamber 50 is in direct alignment for the access passageway 26. The operator then removes the irradiated sample.

FIG. 6 shows a sectional view along lines 66 of FIG. 7 illustrating an alternative turntable drive. The support and rotational assembly for the rotatable block 36 is not shown.

In this modification, instead of using a split drive coupling arrangement to rotate the turntable, the drive assembly rotates with the rotatable block 36.

The turntable 110 is disposed within the radiation chamber 50 and is directly powered for rotational movement by a pulley 112 having a lower end 114 supported in a bearing recess 1 16 of the movable block 36.

A longitudinally extending pulley and belt cavity 1 l8 accommodates a drive belt or chain 120 which extends around pulley 1 l2 and drive pulley 122.

Drive shaft 124 powers the drive pulley 122 and extends down through the rotatable block 36 and through the housing 10. It is surrounded by the transmission shaft housing 126. Drive shaft 124 extends down into the motor and drive assembly shown generally at 128.

The transmission shaft housing 126 and the motor and drive assembly 128 move with the rotatable block 36 when it is rotated. The transmission shaft housing 126 will move in a circular are through the circular arcuate passage 130, shown in dotted outline in F IG. 7.

With this arrangement, there is always a direct mechanical connection with the turntable, and there is no need for a coupling arrangement. Both the motor and the drive shaft assembly turn through an arcuate path which extends along the arcuate passageway through the lower portion of housing 10.

It can be seen that this unit can easily and simply be operated by a single operator; providing for even allround exposure of a sample, without exposing the operator to radiation.

The radiation unit is small, compact and may be portable.

The turntable drive assembly provides for controlled continual exposure of the sample without requiring elaborate remote control equipment.

While the invention has been described, it will be understood that it is capable of further modifications and this application is intended to cover any variations, uses, or adaptations of the invention following in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains, and as may be applied to the essential features hereinbefore set forth and as fall within the scope of the invention or the limits of the appended claims.

What I claim is:

1. An atomic irradiator comprising:

a. a radiation absorbing housing,

b. a radiation absorbing block within said housing, and mounted for rotary movement about a vertical axis,

. a radiation source compartment centrally disposed within said housing immediately adjacent and extending vertically along said movable radiation absorbing block,

d. a radiation chamber within said movable block normally accessible from the exterior of said housing which can be moved into position adjacent said radiation source compartment,

e. said radiation chamber having movable support means for exposing all sides of a sample placed therein to radiation, and

f. said radiation absorbing block being generally cylindrical and being provided with integral radiation absorbing means for rotatably journaling'said block within said radiation housing, said means comprising upper and lower protruberances on said radiation absorbing block providing substantially non-planar upper and lower surfaces thereon.

2. The combination as set forth in claim 1, wherein,

said movable support means includes:

a. turntable assembly disposed within said radiation chamber, and

b. disengageable driving means extending through said housing and adapted to engage said turntable assembly when said radiation chamber faces said radiation source compartment.

3. The combination as set forth in claim 2, wherein:

a. said disengageable driving means includes a spring-biased friction coupling between said housing and said rotatable block.

4. The combination as set forth in claim 2, wherein:

a. said disengageable driving means includes a motor driven shaft which extends through said housing.

5. The combination as set forth in claim 2, wherein:

a. said disengageable driving means includes a spring-biased member connected to said turntable at one end, and

b. a rotatable motor driven shaft which engages the other end of said member.

6. The combination as set forth in claim 5, wherein:

a. said turntable assembly is rotatably mounted on a ball bearing and has a depending shaft,

b. said one end of said spring-biased member telescopically engages said depending shaft.

7. An atomic irradiator comprising:

a. a radiation absorbing housing,

b. a radiation absorbing block within said housing, and mounted for rotary movement about a vertical axis,

c. a radiation source compartment containing an atomic radiation source centrally disposed within said housing immediately adjacent and extending vertically along said movable radiation absorbing block,

d. a radiation chamber within said movable block which can be moved into position adjacent said radiation source compartment,

e. an access opening extending through said housing to which said radiation chamber is rotated to permit samples to be placed in and removed from said radiation chamber, and

f. said radiation absorbing block being generally cylindrical and being provided with integral radiation absorbing means for rotatably joumaling said block within said radiation housing, said means comprising upper and lower protruberances on said radiation absorbing block providing substantially non-planar upper and lower surfaces thereon.

8. The combination as set forth in claim 7, wherein:

a. said radiation chamber has rotatable support means for exposing all sides of the sample disposed within said radiation chamber to the radiation source.

9. An atomic irradiator comprising:

a. a radiation absorbing housing having an internal cavity symmetrical about a vertical axis and extending from adjacent an outer wall to a central interior point,

b. said housing wall having an access passage which extends into said cavity,

c. a radiation source compartment centrally disposed within said housing, immediately adjacent and extending vertically along said internal cavity,

d. a generally cylindrical rotatable block of radiation absorbing material fitted within said cavity and ilififs, $593 f iitihfiliii ig filfifii $61 integral radiation absorbing means for rotatably journaling said block within said radiation housing, said means comprising upper and lower protruberances on said radiation absorbing block providing substantially non-planar upper and lower surfaces thereon,

e. an open radiation chamber recess within the side wall of said rotatable block and being positionable to face said radiation source compartment when said rotatable block is rotated, and

f. rotating sample support means within said radiation chamber for continuously presenting vertical surfaces of a sample contained therein to radiation when said radiation chamber faces said radiation source compartment.

10. The combination as set forth in claim 9, wherein:

a. said sample support means includes a rotatable turntable which has disengageable driving means adapted to engage a drive shaft when said radiation chamber faces said radiation source compartment.

11. The combination as set forth in claim 10,

wherein:

a. said disengageable driving means includes a spring-biased sleeve member telescopically mounted at the bottom of said turntable, and

b. said sleeve means has a lower chamfered surface which engages the top of said turntable drive shaft.

12. The combination as set forth in claim 9, wherein:

a. said rotating sample support means includes a drive mechanism which moves with said rotatable block.

13. The combination as set forth in claim 9, wherein:

a. said drive mechanism includes a pulley and belt drive system which is disposed within said rotatable block.

14. The combination as set forth in claim 9, wherein:

a. said radiation absorbing housing has a vertical arcuate passage extending through to said internal cavity; and

b. transmission drive shaft means extending through said arcuate passage and into said rotatable block to rotate said sample support means.

15. The combination as set forth in claim 9, wherein:

a. said transmission drive shaft means includes a pulley and belt drive system which is disposed within said rotatable block. 

1. An atomic irradiator comprising: a. a radiation absorbing housing, b. a radiation absorbing block within said housing, and mounted for rotary movement about a vertical axis, c. a radiation source compartment centrally disposed within said housing immediately adjacent and extending vertically along said movable radiation absorbing block, d. a radiation chamber within said movable block normally accessible from the exterior of said housing which can be moved into position adjacent said radiation source compartment, e. said radiation chamber having movable support means for exposing all sides of a sample placed therein to radiation, and f. said radiation absorbing block being generally cylindrical and being provided with integral radiation absorbing means for rotatably journaling said block within said radiation housing, said means comprising upper and lower protruberances on said radiation absorbing block providing substantially non-planar upper and lower surfaces thereon.
 2. The combination as set forth in claim 1, wherein, said movable support means includes: a. turntable assembly disposed within said radiation chamber, and b. disengageable driving means extending through said housing and adapted to engage said turntable assembly when said radiation chamber faces said radiation source compartment.
 3. The combination as set forth in claim 2, wherein: a. said disengageable driving means includes a spring-biased friction coupling between said housing and said rotatable block.
 4. The combination as set forth in claim 2, wherein: a. said disengageable driving means includes a motor driven shaft which extends through said housing.
 5. The combination as set forth in claim 2, wherein: a. said disengageable driving means includes a spring-biased member connected to said turntable at one end, and b. a rotatable motor driven shaft which engages the other end of said member.
 6. The combination as set forth in claim 5, wherein: a. said turntable assembly is rotatably mounted on a ball bearing and has a depending shaft, b. said one end of said spring-biased member telescopically engages said depending shaft.
 7. An atomic irradiator comprising: a. a radiation absorbing housing, b. a radiation absorbing block within said housing, and mounted for rotary movement about a vertical axis, c. a radiation source compartment containing an atomic radiation source centrally disposed within said housing immediately adjacent and extending vertically along said movable radiation absorbing block, d. a radiation chamber within said movable block which can be moved into position adjacent said radiation source compartment, e. an access opening extending through said housing to which said radiation chamber is rotated to permit samples to be placed in and removed from said radiation chamber, and f. said radiation absorbing block being generally cylindrical and being provided with integral radiation absorbing means for rotatably journaling said block within said radiation housing, said means comprising upper and lower protruberances on said radiation absorbing block providing substantially non-planar upper and lower suRfaces thereon.
 8. The combination as set forth in claim 7, wherein: a. said radiation chamber has rotatable support means for exposing all sides of the sample disposed within said radiation chamber to the radiation source.
 9. An atomic irradiator comprising: a. a radiation absorbing housing having an internal cavity symmetrical about a vertical axis and extending from adjacent an outer wall to a central interior point, b. said housing wall having an access passage which extends into said cavity, c. a radiation source compartment centrally disposed within said housing, immediately adjacent and extending vertically along said internal cavity, d. a generally cylindrical rotatable block of radiation absorbing material fitted within said cavity and having an axis of rotation coincident with said vertical axis, said rotatable block being provided with integral radiation absorbing means for rotatably journaling said block within said radiation housing, said means comprising upper and lower protruberances on said radiation absorbing block providing substantially non-planar upper and lower surfaces thereon, e. an open radiation chamber recess within the side wall of said rotatable block and being positionable to face said radiation source compartment when said rotatable block is rotated, and f. rotating sample support means within said radiation chamber for continuously presenting vertical surfaces of a sample contained therein to radiation when said radiation chamber faces said radiation source compartment.
 10. The combination as set forth in claim 9, wherein: a. said sample support means includes a rotatable turntable which has disengageable driving means adapted to engage a drive shaft when said radiation chamber faces said radiation source compartment.
 11. The combination as set forth in claim 10, wherein: a. said disengageable driving means includes a spring-biased sleeve member telescopically mounted at the bottom of said turntable, and b. said sleeve means has a lower chamfered surface which engages the top of said turntable drive shaft.
 12. The combination as set forth in claim 9, wherein: a. said rotating sample support means includes a drive mechanism which moves with said rotatable block.
 13. The combination as set forth in claim 9, wherein: a. said drive mechanism includes a pulley and belt drive system which is disposed within said rotatable block.
 14. The combination as set forth in claim 9, wherein: a. said radiation absorbing housing has a vertical arcuate passage extending through to said internal cavity; and b. transmission drive shaft means extending through said arcuate passage and into said rotatable block to rotate said sample support means.
 15. The combination as set forth in claim 9, wherein: a. said transmission drive shaft means includes a pulley and belt drive system which is disposed within said rotatable block. 